* Question: PCM short and long sync formats
@ 2012-03-21 10:21 Omair Mohammed Abdullah
2012-03-21 11:51 ` Mark Brown
0 siblings, 1 reply; 11+ messages in thread
From: Omair Mohammed Abdullah @ 2012-03-21 10:21 UTC (permalink / raw)
To: alsa-devel, broonie
I was looking for PCM short frame sync and PCM long frame sync, but they
are not present in soc-dai.h (FORMAT_MASK). Is there a way to derive
them from other formats or should I just add them?
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: Question: PCM short and long sync formats
2012-03-21 10:21 Question: PCM short and long sync formats Omair Mohammed Abdullah
@ 2012-03-21 11:51 ` Mark Brown
2012-03-26 9:06 ` Omair Mohammed Abdullah
0 siblings, 1 reply; 11+ messages in thread
From: Mark Brown @ 2012-03-21 11:51 UTC (permalink / raw)
To: Omair Mohammed Abdullah; +Cc: alsa-devel
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On Wed, Mar 21, 2012 at 03:51:36PM +0530, Omair Mohammed Abdullah wrote:
> I was looking for PCM short frame sync and PCM long frame sync, but
> they are not present in soc-dai.h (FORMAT_MASK). Is there a way to
> derive them from other formats or should I just add them?
What do you mean when you say "PCM short frame sync" and "PCM long
frame sync"?
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: Question: PCM short and long sync formats
2012-03-21 11:51 ` Mark Brown
@ 2012-03-26 9:06 ` Omair Mohammed Abdullah
2012-03-26 10:26 ` Mark Brown
0 siblings, 1 reply; 11+ messages in thread
From: Omair Mohammed Abdullah @ 2012-03-26 9:06 UTC (permalink / raw)
To: Mark Brown; +Cc: alsa-devel
On Wednesday 21 March 2012 05:21 PM, Mark Brown wrote:
> On Wed, Mar 21, 2012 at 03:51:36PM +0530, Omair Mohammed Abdullah wrote:
>
>> I was looking for PCM short frame sync and PCM long frame sync, but
>> they are not present in soc-dai.h (FORMAT_MASK). Is there a way to
>> derive them from other formats or should I just add them?
>
> What do you mean when you say "PCM short frame sync" and "PCM long
> frame sync"?
Sorry for the late reply, I was away.
What I mean by short/long frame sync is: the frame sync lasts for 1
bit/1 word wide.
Eg.: For short frame sync, we get a frame sync signal for 1 clock before
the first bit on the RX/TX.
It is different from I2S mode where the frame sync is inverted and the
transition starts 1 clock before the bits and lasts till bit 1.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: Question: PCM short and long sync formats
2012-03-26 9:06 ` Omair Mohammed Abdullah
@ 2012-03-26 10:26 ` Mark Brown
2012-03-26 12:07 ` Omair Mohammed Abdullah
0 siblings, 1 reply; 11+ messages in thread
From: Mark Brown @ 2012-03-26 10:26 UTC (permalink / raw)
To: Omair Mohammed Abdullah; +Cc: alsa-devel
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On Mon, Mar 26, 2012 at 02:36:53PM +0530, Omair Mohammed Abdullah wrote:
> On Wednesday 21 March 2012 05:21 PM, Mark Brown wrote:
> >What do you mean when you say "PCM short frame sync" and "PCM long
> >frame sync"?
> Sorry for the late reply, I was away.
> What I mean by short/long frame sync is: the frame sync lasts for 1
> bit/1 word wide.
> Eg.: For short frame sync, we get a frame sync signal for 1 clock
> before the first bit on the RX/TX.
> It is different from I2S mode where the frame sync is inverted and
> the transition starts 1 clock before the bits and lasts till bit 1.
I'm sorry but I still have no idea what you're talking about. You've
described PCM mode but not explained what "short frame sync" and "long
frame sync" mode are.
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: Question: PCM short and long sync formats
2012-03-26 10:26 ` Mark Brown
@ 2012-03-26 12:07 ` Omair Mohammed Abdullah
2012-03-26 12:08 ` Mark Brown
0 siblings, 1 reply; 11+ messages in thread
From: Omair Mohammed Abdullah @ 2012-03-26 12:07 UTC (permalink / raw)
To: Mark Brown; +Cc: alsa-devel
On Monday 26 March 2012 03:56 PM, Mark Brown wrote:
> On Mon, Mar 26, 2012 at 02:36:53PM +0530, Omair Mohammed Abdullah wrote:
>> On Wednesday 21 March 2012 05:21 PM, Mark Brown wrote:
>
>>> What do you mean when you say "PCM short frame sync" and "PCM long
>>> frame sync"?
>
>> Sorry for the late reply, I was away.
>
>> What I mean by short/long frame sync is: the frame sync lasts for 1
>> bit/1 word wide.
>
>> Eg.: For short frame sync, we get a frame sync signal for 1 clock
>> before the first bit on the RX/TX.
>
>> It is different from I2S mode where the frame sync is inverted and
>> the transition starts 1 clock before the bits and lasts till bit 1.
>
> I'm sorry but I still have no idea what you're talking about. You've
> described PCM mode but not explained what "short frame sync" and "long
> frame sync" mode are.
This diagram may explain things better:
http://picpaste.com/pcm_fs-7dBlrkuW.png
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: Question: PCM short and long sync formats
2012-03-26 12:07 ` Omair Mohammed Abdullah
@ 2012-03-26 12:08 ` Mark Brown
2012-03-26 13:29 ` Omair Mohammed Abdullah
0 siblings, 1 reply; 11+ messages in thread
From: Mark Brown @ 2012-03-26 12:08 UTC (permalink / raw)
To: Omair Mohammed Abdullah; +Cc: alsa-devel
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On Mon, Mar 26, 2012 at 05:37:15PM +0530, Omair Mohammed Abdullah wrote:
> On Monday 26 March 2012 03:56 PM, Mark Brown wrote:
> >I'm sorry but I still have no idea what you're talking about. You've
> >described PCM mode but not explained what "short frame sync" and "long
> >frame sync" mode are.
> This diagram may explain things better:
> http://picpaste.com/pcm_fs-7dBlrkuW.png
Sorry, that's not really clarifying things. It looks like "long frame
sync" is just I2S but presumably there's some difference?
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^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: Question: PCM short and long sync formats
2012-03-26 12:08 ` Mark Brown
@ 2012-03-26 13:29 ` Omair Mohammed Abdullah
2012-03-26 13:33 ` Mark Brown
0 siblings, 1 reply; 11+ messages in thread
From: Omair Mohammed Abdullah @ 2012-03-26 13:29 UTC (permalink / raw)
To: Mark Brown; +Cc: alsa-devel
On Monday 26 March 2012 05:38 PM, Mark Brown wrote:
> On Mon, Mar 26, 2012 at 05:37:15PM +0530, Omair Mohammed Abdullah wrote:
>> On Monday 26 March 2012 03:56 PM, Mark Brown wrote:
>
>>> I'm sorry but I still have no idea what you're talking about. You've
>>> described PCM mode but not explained what "short frame sync" and "long
>>> frame sync" mode are.
>
>> This diagram may explain things better:
>> http://picpaste.com/pcm_fs-7dBlrkuW.png
>
> Sorry, that's not really clarifying things. It looks like "long frame
> sync" is just I2S but presumably there's some difference?
Yes, in I2S mode, according to the spec I have, the frame sync leads the
MSB of the data by 1 bit clock cycle. Whereas the 'long frame sync' mode
starts with the MSB of the data.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: Question: PCM short and long sync formats
2012-03-26 13:29 ` Omair Mohammed Abdullah
@ 2012-03-26 13:33 ` Mark Brown
2012-03-27 3:32 ` [PATCH] ASoC: Added PCM short and long frame " Omair Mohammed Abdullah
0 siblings, 1 reply; 11+ messages in thread
From: Mark Brown @ 2012-03-26 13:33 UTC (permalink / raw)
To: Omair Mohammed Abdullah; +Cc: alsa-devel
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On Mon, Mar 26, 2012 at 06:59:43PM +0530, Omair Mohammed Abdullah wrote:
> On Monday 26 March 2012 05:38 PM, Mark Brown wrote:
> >Sorry, that's not really clarifying things. It looks like "long frame
> >sync" is just I2S but presumably there's some difference?
> Yes, in I2S mode, according to the spec I have, the frame sync leads
> the MSB of the data by 1 bit clock cycle. Whereas the 'long frame
> sync' mode starts with the MSB of the data.
This is probably left justified mode but I'm really not clear what
your question is here. Please ask a *specific* question, with reference
to what you find unclear in the code.
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^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH] ASoC: Added PCM short and long frame sync formats
2012-03-26 13:33 ` Mark Brown
@ 2012-03-27 3:32 ` Omair Mohammed Abdullah
2012-03-27 3:34 ` Omair Mohammed Abdullah
0 siblings, 1 reply; 11+ messages in thread
From: Omair Mohammed Abdullah @ 2012-03-27 3:32 UTC (permalink / raw)
To: alsa-devel; +Cc: broonie, lrg, Omair Mohammed Abdullah
The PCM short frame sync sends a short (1 clock length) sync signal before the
MSB of data. The PCM long frame sync sends a 1 word length sync signal along
with the data.
Signed-off-by: Omair Mohammed Abdullah <omair.m.abdullah@linux.intel.com>
---
include/sound/soc-dai.h | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/include/sound/soc-dai.h b/include/sound/soc-dai.h
index c429f24..dc94b25 100644
--- a/include/sound/soc-dai.h
+++ b/include/sound/soc-dai.h
@@ -32,6 +32,8 @@ struct snd_soc_dapm_widget;
#define SND_SOC_DAIFMT_DSP_B 5 /* L data MSB during FRM LRC */
#define SND_SOC_DAIFMT_AC97 6 /* AC97 */
#define SND_SOC_DAIFMT_PDM 7 /* Pulse density modulation */
+#define SND_SOC_DAIFMT_SHORT_SYNC 8 /* FRM for 1 clock before MSB */
+#define SND_SOC_DAIFMT_LONG_SYNC 9 /* FRM for 1 word starting with MSB */
/* left and right justified also known as MSB and LSB respectively */
#define SND_SOC_DAIFMT_MSB SND_SOC_DAIFMT_LEFT_J
--
1.7.4.1
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH] ASoC: Added PCM short and long frame sync formats
2012-03-27 3:32 ` [PATCH] ASoC: Added PCM short and long frame " Omair Mohammed Abdullah
@ 2012-03-27 3:34 ` Omair Mohammed Abdullah
2012-03-27 7:33 ` Lars-Peter Clausen
0 siblings, 1 reply; 11+ messages in thread
From: Omair Mohammed Abdullah @ 2012-03-27 3:34 UTC (permalink / raw)
To: Omair Mohammed Abdullah; +Cc: alsa-devel, broonie, lrg
On Tuesday 27 March 2012 09:02 AM, Omair Mohammed Abdullah wrote:
> The PCM short frame sync sends a short (1 clock length) sync signal before the
> MSB of data. The PCM long frame sync sends a 1 word length sync signal along
> with the data.
>
> Signed-off-by: Omair Mohammed Abdullah<omair.m.abdullah@linux.intel.com>
> ---
> include/sound/soc-dai.h | 2 ++
> 1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/include/sound/soc-dai.h b/include/sound/soc-dai.h
> index c429f24..dc94b25 100644
> --- a/include/sound/soc-dai.h
> +++ b/include/sound/soc-dai.h
> @@ -32,6 +32,8 @@ struct snd_soc_dapm_widget;
> #define SND_SOC_DAIFMT_DSP_B 5 /* L data MSB during FRM LRC */
> #define SND_SOC_DAIFMT_AC97 6 /* AC97 */
> #define SND_SOC_DAIFMT_PDM 7 /* Pulse density modulation */
> +#define SND_SOC_DAIFMT_SHORT_SYNC 8 /* FRM for 1 clock before MSB */
> +#define SND_SOC_DAIFMT_LONG_SYNC 9 /* FRM for 1 word starting with MSB */
>
> /* left and right justified also known as MSB and LSB respectively */
> #define SND_SOC_DAIFMT_MSB SND_SOC_DAIFMT_LEFT_J
What I am looking for is something like this. But
SND_SOC_DAIFMT_SHORT_SYNC might be the same as SND_SOC_DAIFMT_DSP_A.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] ASoC: Added PCM short and long frame sync formats
2012-03-27 3:34 ` Omair Mohammed Abdullah
@ 2012-03-27 7:33 ` Lars-Peter Clausen
0 siblings, 0 replies; 11+ messages in thread
From: Lars-Peter Clausen @ 2012-03-27 7:33 UTC (permalink / raw)
To: Omair Mohammed Abdullah; +Cc: alsa-devel, broonie, lrg
On 03/27/2012 05:34 AM, Omair Mohammed Abdullah wrote:
> On Tuesday 27 March 2012 09:02 AM, Omair Mohammed Abdullah wrote:
>> The PCM short frame sync sends a short (1 clock length) sync signal before the
>> MSB of data. The PCM long frame sync sends a 1 word length sync signal along
>> with the data.
>>
>> Signed-off-by: Omair Mohammed Abdullah<omair.m.abdullah@linux.intel.com>
>> ---
>> include/sound/soc-dai.h | 2 ++
>> 1 files changed, 2 insertions(+), 0 deletions(-)
>>
>> diff --git a/include/sound/soc-dai.h b/include/sound/soc-dai.h
>> index c429f24..dc94b25 100644
>> --- a/include/sound/soc-dai.h
>> +++ b/include/sound/soc-dai.h
>> @@ -32,6 +32,8 @@ struct snd_soc_dapm_widget;
>> #define SND_SOC_DAIFMT_DSP_B 5 /* L data MSB during FRM LRC */
>> #define SND_SOC_DAIFMT_AC97 6 /* AC97 */
>> #define SND_SOC_DAIFMT_PDM 7 /* Pulse density modulation */
>> +#define SND_SOC_DAIFMT_SHORT_SYNC 8 /* FRM for 1 clock before MSB */
>> +#define SND_SOC_DAIFMT_LONG_SYNC 9 /* FRM for 1 word starting with MSB */
>>
>> /* left and right justified also known as MSB and LSB respectively */
>> #define SND_SOC_DAIFMT_MSB SND_SOC_DAIFMT_LEFT_J
>
> What I am looking for is something like this. But
> SND_SOC_DAIFMT_SHORT_SYNC might be the same as SND_SOC_DAIFMT_DSP_A.
Yes it is. And if you really only have two slots your long sync is
SND_SOC_DAIFMT_LEFT_J, but with the bit clock inverted.
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2012-03-27 7:41 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-03-21 10:21 Question: PCM short and long sync formats Omair Mohammed Abdullah
2012-03-21 11:51 ` Mark Brown
2012-03-26 9:06 ` Omair Mohammed Abdullah
2012-03-26 10:26 ` Mark Brown
2012-03-26 12:07 ` Omair Mohammed Abdullah
2012-03-26 12:08 ` Mark Brown
2012-03-26 13:29 ` Omair Mohammed Abdullah
2012-03-26 13:33 ` Mark Brown
2012-03-27 3:32 ` [PATCH] ASoC: Added PCM short and long frame " Omair Mohammed Abdullah
2012-03-27 3:34 ` Omair Mohammed Abdullah
2012-03-27 7:33 ` Lars-Peter Clausen
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